Simplified Pipe/Pump Sizing Chart (Copper Tubing)
Copper Pipe & Pump Sizing
Pipe Size |
BTUH |
Friction Head Feet 100’ (straight pipe) |
Friction Head Feet 100’ (allowance for fittings and boiler) |
Gallons per Minute (GPM) at 20 degree Delta T |
1/2” |
17,000 |
4.2’ |
6’ |
1.7 |
3/4” |
39,000 |
4.2’ |
6’ |
3.9 |
1” |
71,000 |
4.2’ |
6’ |
7.1 |
1-1/4” |
160,000 |
4.2’ |
6’ |
16.0 |
1-1/2” |
240,000 |
4.2’ |
6’ |
24.0 |
2” |
450,000 |
4.2’ |
6’ |
45.0 |
2-1/2” |
750,000 |
4.2’ |
6’ |
75.0 |
3” |
1,400,000 |
4.2’ |
6’ |
140.0 |
4” |
2,900,000 |
4.2’ |
6’ |
290.0 |
In order for a pump to obtain the above GPM, the pump must be sized properly to overcome the friction head of 4.2-6 feet per 100’ of copper pipe.
Example: For water to move 7.1 gallons per minute through a 1” pipe that is 200’, the pump must be able to overcome the friction loss of 4.2’-6.0’ per 100’ (4.2’-6.0’ x 2=8.4-12.0 feet). The pump will need to be able to move 7.1 GPM with a 8.4-12 friction head.